Serie ECO T Threaded end back flow preventer with controllable reduced pressure zone BRANDONI made in E U R O P E Application fields WATER FIRE FIGHTING DRINKING WATER 74 www.brandoni.it
Serie ECO T The threaded end backflow ECO F preventers, with controllable reduced pressure zone type BA EN77 are approved in conformity with EN2729 and are manufactured in accordance with the most severe product norms and in conformity with the quality requirements of EN ISO 900. The body of dimension DN 5 is made of brass and the body of dimensions DN 20-50 is made of bronze. They consist of 2 spring check valves and a chamber situated in between the spring check valves, which contain a security valve, which in the event of backflow, isolates the primary network from the user network. The backflow might be caused by siphoning (the entry pressure decreases due to ruptures in the piping upstream, the water supply is interrupted, draining off parts of the piping due to events upstream) or the build up of counter pressure (the pressure of the user network is higher than the pressure in the primary network due to overpressure caused, for example, by incoming water pumped from a private water well). Backflow preventers are indispensable to prevent contamination of the distribution network of the drinking water from connect user units (for example, washing machines, boilers, industrial plants, hospitals, laboratories, fire fighting plants). For correct installation, it is necessary to install a filter upstream with respect to the backflow preventer, in order to avoid problems caused by dirt and residual parts present in the piping, such as shut-off valves upstream and downstream with respect to the backflow preventer. Series ECOT backflow preventer, even if marked PN0 for the purposes of reference normative EN2729, due to its design and testing characteristics is suitable for installation in firefighting networks with service presure of 2 bar. 2. Very compact design, one of the shortest backflow preventers, which allows easy installation in limited spaces. 2. Test points fitted with mini-valves, for checking the absolute and the differential pressure in the upstream and intermediate areas. Together with the ECO TEST, these allow verifying the function of the backflow preventer.. DN 20-50: Easy maintenance due to removable cover. Accessories Special version ECO TEST: control instrument Pre-assembled unit Refer to specifications on page 80 In conformity with EN77, BA type Homologated in accordance to EN2729 Construction and testing norms (correspondences): Threading: ISO228/ Marking: EN9 Testing: 00% testing in accordance with EN2729 www.brandoni.it 75
Threaded end back flow preventer with controllable reduced pressure zone Serie ECO T - DN 5 0, 5 6 4 R S. S. S.2 8 7 9 S.5 S.7, S.8 2 S.4 Materials 2 4 5 6 7 8 9 0 2 R.. S. S.2 S. S.4 S.5 S.6 S.7 S.8 Component Body Bonnet Valve M/F ¼ Connection Ring nut Gasket Spring Downstream check valve bearing Retaining ring Spacer Circlip DIN 472 Drain conveyor Upstream check valve Downstream check valve Manifold Shutter guide Relief valve seal Relief valve Shutter Membrane Relief valve spring Hex nut Membrane bearing plate O-ring Nuts and Bolts Material Brass OT P/Zn40Pb2 EPDM AISI 04 Polypropylene POM POM PPO Noryl Silicon rubber Neoprene + Nylon NBR AISI 04 76 www.brandoni.it
Serie ECO T Serie ECO T - DN 20 50 2 S. S.2 S. S.4 4 5 6 R. R.6 R.7 R.2 R. S.5.8..2..6 R.5 R.4.4.5.7 S.7 S.9 S.8 S.6 7 Materials 2 4 5 6 7 R. R.2 R. R.4 R.5 R.6 R.7..2..4.5.6.7.8 S. S.2 S. S.4 S.5 S.6 S.7 S.8 S.9 Component Body Bonnet Valve M/F ¼ Connection Ring nut Gasket Drain conveyor Upstream check valve seat Upstream check valve flange Upstream check valve shutter Upstream check valve spring Upstream check valve stem Upstream check valve seal Upstream check valve retaining ring Downstream check valve seat Downstream check valve flange Downstream check valve shutter Downstream check valve spring Downstream check valve stem Downstream check valve stem guide Downstream check valve seal Downstream check valve retaining ring Equalizer Equalizer bush Equalizer cap Membrane Stem Relief valve shutter Relief valve spring Relief valve seat Relief valve seal O-ring Nuts and bolts Material Bronze CuSn5Zn5Pb5 EN 982 Bronze CuSn5Zn5Pb5 EN 982 Brass OT P/Zn40Pb2 CELFLEx Polypropylene PPO Noryl Silicon rubber Bronze CuSn5Zn5Pb5 EN 982 Silicon rubber PPO Noryl PTFE + carbon OT P/Zn40Pb2 Neoprene + Nylon PPO Noryl PPO Noryl Silicon rubber NBR AISI 04 www.brandoni.it 77
Threaded end back flow preventer with controllable reduced pressure zone Serie ECO T - DN 5 Serie ECO T - DN 20 50 A W A W T N H H T N H H S S S2 S Dimensions (mm) DN 5 20 25 2 40 50 T ISO 228- /2" /4/" " " /4 " /2 2" A 74 258 258 57 57 428 H 58 07 07 40 40 59 H 69 86 86 20 20 24 N 58 55 55 75 75 88 W 68 06 06 46 46 8 S/2/ 50 6 75/90/20 Weight (kg) DN 5 20 25 2 40 50 kg,45 4 4 9 9 Serie ECO T pre-assembled unit Bv G G Hmax A Dimensions (mm) DN 5 20 25 2 40 50 G 5 45 57 58 66 78 G 70 90 0 20 40 60 A 5 448 479 62 658 78 H max unit 58 07 07 40 40 59 Bv 00 5 5 50 50 80 kg 2 5 6 2,6 8,4 78 www.brandoni.it
Serie ECO T Maximum pressure Temperature Pressure 0 bar Temperature min C Max C 0 65 Head loss Fluid: water (m H2O = 0,098bar) bar.5 DN5 DN20 DN25 DN2 DN40 DN50 0.5 0.6 0 mc/h Kv - DN chart DN 5 20 25 2 40 50 Kv,76 6,7 9,7,5 25 8,6 Minimum flow rate (mc/h) in function of head loss ( accorging to EN 2729:2002 ) DN 5 20 25 2 40 50 Head loss bar,9,4 5, 8,7,6 2,2 Head loss,5 bar 2,9 5, 7,9/ 20, 2,8 www.brandoni.it 79
Threaded end back flow preventer with controllable reduced pressure zone Versions Back flow preventer ECO T DN5 ECO T DN20 50 Body: Brass ADZ Temp: 0 +65 C Body: Bronze Temp: 0 +65 C Accessories ECO TEST Control instrument. Composed of instruments, pre-assembled circuit, accessories for connection to the valve and the instructions for the testing of the correct working of the back flow preventer. Special version Pre-assembled unit Unit composed of 2 shut-off valves ( ball valves, butterfly valves or gate valves), filter, back flow preventer VALVE VALVE BACk FLOW PREVENTER FILTER 80 www.brandoni.it
Instruction and Recommendations Serie ECO T The information provided here is delivered with each product, and contains Instruction for use and maintenance ; it is also available on our website: www.brandoni.it (download section) OPERATING PRINCIPLE R NORMAL OPERATION: REGULAR FLOW Under normal conditions the relief valve is closed and water flows through the 2 check valves (R and ). Due to the head loss of valve, the pressure in the intermediate section is at least 40 millibar less than the upstream pressure. This difference acts upon the membrane and closes the relief valve S. S NO FLOW: NORMAL PRESSURE The check valves ( and 2) are closed and the relief valve remains closed. BACK PRESSURE: DOWNSTREAM OVERPRESSURE The downstream check valve () closes, preventing potentially contaminated water from flowing into the supply pipe. If the downstream check valve is not perfectly watertight, the polluted water can seep into the central chamber. As the pressure in the central chamber increases, the relief valve opens and the polluted fluid discharges. BACK-SIPHONAGE: UPSTREAM DEPRESSION If the upstream pressure accidentally decreases, the check valves ( and 2) automatically close; so the pressure difference between the upstream section and the central section is reduced; the spring opens the relief valve and the central chamber empties. Consequently, the flow between the upstream area and the downstream area is interrupted, making it completely safe. The empting of the central chamber causes a fall in pressure and brings the valve back to the initial safety conditions. www.brandoni.it 8
Threaded end back flow preventer with controllable reduced pressure zone IMPORTANT: PRIOR TO INSTALLATION A correct example of how to install the backflow preventer is shown in Fig. A.. The device must be located in a common, easily accessible area of the building, it must be ventilated and not subject to flooding. (The preventer should preferably be placed outside the building works and above the soil). 2. The backflow preventer must be located away from every area that may be flooded, always considering the highest level that water may reach in adjacent areas, in case of frequent flooding.. Around the device, there must be enough room to enable easy installation or removal. It must be easily accessible for repair work and working tests. Maximum hight for water mains and drains FLOOR 4. When the device is placed in an installation which may pollute the drinking water supply network, all networks supplying sanitary or food processing systems must be installed upstream with respect to the backflow preventer and the downstream network must be marked with the conventional safety signs and colours, in accordance with UNI 564P regulations. 5. The opening of relief valve must enable the water to drain off as a result of gravity. 6. When running a test with the ECOTEST device, pressure gauges must be at the same height as the backflow, to ensure correct measurement by the differential pressure gauge. 7. The discharge device must not give off toxic fumes into the room. The discharged waters must not be harmful to the environment: the health authorities should be consulted in the cases established by the current regulations. 8. The leakage recovery system, located under the bleed valve outlet, and the discharge water recovery works, must have a minimum section, corresponding to the following values: FIG. A Drains Water mains 0.5m min 0,5m min 60 CEILING Discharge to drains 0,5 -,5m DN /2 /4 /4 /2 2 Internal diameter of drain pipe 50 6 75 / 90 / 20 INSTALLATION Follow the directions as shown in Fig B. FIG. B. Install an interception valve x upstream with respect to the backflow preventer. 2. Install an interception valve y downstream with respect to the backflow preventer.. When the valves are closed, install a strainer with a bleed plug upstream with respect to the preventer, making sure that water flows in the direction indicated on the body. WARNING. The strainer is essential if the preventer is to work properly. Make sure that, during the installation, there are no residual parts in the pipes that could seriously damage the device. 4. Install the backflow preventer between the strainer and the downstream valve, always following the direction displayed on the product. 5. Close valves -2-6. Remove the plastic protection cap located under the bleed valve. 7. Fix the bleed pipe. 8. Slowly open the upstream valve X. 9. Slowly open the preventer valves following the -2- order, from downstream to up upstream, let them bleed and close. 0. Slowly open the downstream valve Y.. The backflow preventer is now working. Make sure that the relief valve does not leak. In case of leakage, check if there are pressure decreases in the upstream section. 82 www.brandoni.it
Serie ECO T MAINTENANCE DN 5 MAINTENANCE OF THE BLEED VALVE - Unscrew the bonnet bolts - Take out and replace the CLOSING DEVICE S MAINTENANCE DN 20 50 MAINTENANCE OF THE BLEED VALVE - Unscrew the bonnet bolts - Take out and replace the CLOSING DEVICE S S S EXTRACTION OF THE CHECK VALVES - Remove end connections - Remove the circlips - Remove the bonnet and the closing device - Acting in the directions shown by arrows, remove the upstream check valve R and the downstream check valve MAINTENANCE OF THE UPSTREAM CHECK VALVE - Remove the retaining ring and take out the shutter of upstream valve R - Unscrew the nut - Replace the seal R R ASSEMBLING THE VALVES - Acting in the directions shown by arrows, replace the upstream check valve R and downstream check valve - Put the circlips in place - Put the closing DEVICE S in place and mount the bonnet - Reassemble the end connections MAINTENANCE OF THE DOWNSTREAM CHECK VALVE - Remove the retaining ring and take out the upstream valve - Unscrew the nut - Replace the seal R SPARE PARTS (CODES) SPARE PARTS R S ECOT - DN5 K005900C70 K00590C70 K005998C70 SPARE PARTS (CODES) SPARE PARTS ECOT.020 ECOT.025 ECOT.02 ECOT.040 ECOT.50 R K00996C70 K05996C70 K020996C70 K00997C70 K05997C70 K020997C70 S K00998C70 K05998C70 K020998C70 Upstream valve seal 0007C70 0507C70 02007C70 Downstream valve seal 00078C70 05078C70 020078C70 www.brandoni.it 8